Kurzfassung

A robot manipulator sharing its workspace with
humans should be able to quickly detect collisions and safely
react for limiting injuries due to physical contacts. In the absence
of external sensing, relative motions between robot and human
are not predictable and unexpected collisions may occur at
any location along the robot arm. Based on physical quantities
such as total energy and generalized momentum of the robot
manipulator, we present an efficient collision detection method
that uses only proprioceptive robot sensors and provides also
directional information for a safe robot reaction after collision.
The approach is first developed for rigid robot arms and then
extended to the case of robots with elastic joints, proposing
different reaction strategies. Experimental results on collisions
with the DLR-III lightweight manipulator are reported.